One piece low profile securing latch

ABSTRACT

A securing ring for holding a lid or similar closure on a container has a latch lever which is movable between an open position in which first and second ends of the ring are separated and a closed position in which the first and second ends are drawn closer together. The latch lever is connected to the first end of the ring by a flexible connection such as a living hinge or ligament. The latch lever in the closed position is at least partially overlappingly received against the first end of the ring. The latch lever may be connected to the ring second end by a pivotable connection of various forms and preferably operates with an overcentre action. Arrangements for stress transfer directly between the closed ring ends are also described. The resulting latch mechanisms are of low profile and may be moulded from plastics materials.

FIELD OF THE INVENTION

This invention concerns a latched securing ring for holding a lid or similar closure on a container, the ring for example being of the kind having an inwardly facing, circumferentially extending groove arranged to trap a rim of the lid/closure and also trap a peripheral flange or similar radial extension(s) provided around an opening in the container. In this way the lid rim and container flange are locked together.

INVENTION BACKGROUND

Where the ring is re-useable, it is typically openable to allow installation over or removal from the flange and rim. Then the ring will usually comprise a circumferential discontinuity which forms a pair of overlappable or opposed ends which are releasably secured together by a latch mechanism. The groove profile will often be tapered, to draw the flange and rim into engagement with each other as the ring is tightened, and optionally to draw the flange and rim into clamping engagement with an interposed sealing gasket. However such clamping and/or sealing functions need not always be present. Optionally, the ring latch mechanism may be provided with an anti-tamper lock pin or similar tamper indicating security seal or tag, to provide some guarantee of the integrity of the container contents. The container and its opening may be of various sizes and shapes, with lids or other closures of a suitable corresponding size and shape. For example the opening and lid may be substantially square, rectangular or other polygonal shape. Typically the lid or closure is round, for fitment to an open-ended cylindrical drum. In the North American market, fibreboard drums with steel end chimes are commonly used together with injection moulded lids. Open-topped blow-moulded plastics drums are also used, again with injection moulded plastics lids. The blow moulded drums predominate in other markets.

Historically the openable securing rings have been made from metal, commonly painted or plated steel. However these are difficult to recycle and are prone to corrosion, or to flaking of the coating. Corrosion or coating particles shed by the ring can contaminate the container contents. There is therefore an increasing use of securing rings made from plastics. U.S. Pat. No. 4,194,772, U.S. Pat. No. 4,678,216, U.S. Pat. No. 5,129,537, U.S. Pat. No. 5,713,482, U.S. Pat. No. 7,243,962 and US2009/0294449 relate to such plastics securing rings. US2006/022395 to Kuzelka discloses a locking belt used to secure a removable lid on a drum. The belt is formed from plastics and comprises a first end to which an arcuate handle is secured by an elongate flexible strap. Together the handle and strap form parts of a latch mechanism which can be used to draw a second end of the belt into overlapping interengagement with the first end. When the latch mechanism is closed, the handle overlies a portion of the belt remote from the interengaged belt ends. In this general layout, Kuzelka's latch mechanism therefore resembles many three-part latched metal securing rings of the prior art. The flexible strap however extends radially outwardly across the interengaged ends when the lever is in the closed position. It then also overlies a pivotable connection, by which the lever is mounted to the belt rearwardly of the second end. This latch mechanism is therefore quite extensive, both radially and circumferentially of the belt. In a conventional three-part metal latch mechanism, the equivalent component to the flexible strap is generally a wire loop which is more compact than the strap, and is able to lie to either side of (rather than radially overlying) the interengaged ring ends and the lever pivot in the closed position, to provide an overcentre, stably closed latch condition. A separate hook, snap-engageable in an aperture formed in the handle, is required in order to secure Kuzelka's handle in its closed position.

To be strong enough to survive normal rough handling of the filled containers, plastics securing rings need to be made with a heavier (thicker) cross-section than a corresponding metal ring. Similarly, the latch mechanism for the openable ring ends tends to be significantly bulkier in a plastics ring compared to a metal ring. This can lead to a number of problems. One group of problems arises when the bulkier latch protrudes radially from the container to a significant degree. This limits the relative orientations in which the containers can be packed closely together side by side during transport or storage. Drums are also often moved short distances by turning them on their side and rolling them, e.g. to move them along the length of a truck trailer during loading and unloading. A highly protruding latch is not only prone to mechanical damage, but will also prevent the drum from rolling in a straight line. Some existing plastics latch designs protrude to an extent which prevents the containers from being rolled along the length of a typical truck trailer without running into, or falling off, the trailer sides. A latch which protrudes excessively in the ring axial direction can also interfere with stable stacking of containers one upon the other, and is prone to axial crushing as a result of such stacking and interference. There is therefore a need to provide a securing ring latch capable of being moulded from plastics material, which is of compact design and yet which is able to withstand the rigours of rough treatment to be expected in normal use.

SUMMARY OF THE INVENTION

The present invention provides a securing ring for holding a lid or similar closure on a container, the securing ring comprising:

a first end;

a second end;

a latch lever movable between an open position in which the first and second ends are separated and a closed position in which the first and second ends are drawn closer together, and

a flexible connection by which the latch lever is connected to the first end;

the latch lever being at least partially overlappingly received against the first end in the closed position.

The securing ring is therefore able to be formed from plastics or similar mouldable materials, with the flexible connection allowing the latch lever to be formed together with the remainder of the ring as a single piece. At the same time, the overlapping configuration of the latch lever and the first end of the ring can be made compact, despite the heavier sections necessary in securing rings made from plastics as compared to those formed from metal.

The flexible connection may take various forms. For example, the flexible connection may comprise a so-called “living hinge”, i.e. a flexure bearing formed from the same material as, and continuous with, the first end of the ring and the latch lever. The living hinge preferably comprises a short span, flexible web extending along the hinge axis and spanning between the first end of the ring and the latch lever. Such a living hinge may be readily and cheaply formed together with the latch lever and remainder of the ring in a single moulding operation. By suitable design and choice of materials well known to those skilled in the art, a living hinge can operate over many thousands of cycles without fatigue failure, and provides a compact, low profile, low friction, no wear, flexible connection between the latch lever and ring first end. Alternatively, the flexible connection may comprise at least one flexible strap. For example the flexible strap may comprise a ligament integrally moulded so as to be of the same material as, and continuous with, the first end of the ring and the latch lever. Alternatively, the flexible strap may comprise a ligament insert moulded so as to interconnect the first end of the ring and the latch lever.

The flexible connection may be provided at a distal end of a circumferential extension of the first end of the ring. For example, the ring may comprise a radially outer wall and a pair of side walls which define between them a radially inwardly open, circumferential groove. The circumferential extension may form a continuation of the radially outer wall at the first end of the ring. Alternatively, the circumferential extension may form a continuation of the pair of side walls at the first end of the ring. By making the securing ring and latch lever as a single piece, manufacturing costs can be reduced in comparison to those for a two-piece lockband. Secondary capital is reduced for the tooling or processing for a separate latch lever. Direct labour costs are reduced by eliminating the post-moulding assembly operation of mounting the latch lever to the ring first end. The number of overlapping layers in the region of the latch lever when in its closed position may also be minimised, thereby reducing the bulk of the securing ring latch mechanism, in the ring radial direction, and/or in the ring axial direction.

Preferably the flexible connection allows angular movement of the latch lever through at least 120 degrees, more preferably at least 140 degrees, with respect to the first end. This results in a correspondingly greater range of expansion of the securing ring as the latch lever is moved towards the open position, allowing the securing ring to be more easily installed or removed from around a container opening and container lid, in comparison to a more restricted range of angular movement of the lever, e.g. of 90 degrees or less.

The latch lever may be pivotally connected to the second end of the ring, for example by a pivot connection comprising a pivot shaft rotationally received in a pivot bearing. The pivot bearing may comprise a hook-shaped formation formed on a radially outer surface of the second end of the ring. Advantageously, with the lever in the closed position, the pivotal connection between the latch lever and the second end of the ring lies radially outwardly of the flexible connection, whereby the line of action of hoop stress induced tensile force in the flexible connection extends radially inward of the pivotal connection, and the latch lever operates with an overcentre action.

Alternatively, the latch lever may be pivotally connected to the second end of the ring by any other suitable form of pivotable connection, for example by a knife-edge bearing or a curled lip receivable in a curved slot.

The above and other preferred features and advantages of the invention are further described below with reference to illustrative embodiments of the invention shown in the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded perspective view showing an open topped fibreboard drum together with a polymeric closure lid and an openable polymeric securing ring embodying the present invention;

FIGS. 2 a and 2 b correspond to FIG. 1 but respectively show a side view and a top plan view of the lid secured across the drum opening by means of the securing ring;

FIG. 3 is an enlarged section taken on line 3-3 in FIG. 2 b;

FIG. 4 is an enlarged perspective view of the securing ring of the preceding figures, shown in the closed condition;

FIGS. 5-7 correspond to FIG. 4, but show the ring in radial (latch towards the observer), axial, and radial (latch away from the observer) views respectively;

FIGS. 8 and 9 are further radial views of the ring, respectively taken on arrows 8 and 9 in FIG. 6;

FIG. 10 is a partial sectional view showing the ring latch mechanism, taken on line 10-10 in FIG. 8;

FIG. 11 is a partial sectional view showing the ring latch mechanism, taken on line 11-11 in FIG. 8, and

FIGS. 12 and 13 are views taken axially of the ring, showing the latch mechanism in its open condition, FIG. 12 showing pivot connection components interengaged and FIG. 13 showing pivot connection components disengaged;

FIG. 14 is a cross-sectional view of a ring latch mechanism forming a second embodiment of the invention;

FIGS. 14 a and 14 b are scrap views showing a portion of FIG. 14 drawn to a larger scale;

FIG. 15 is a partial cross-sectional view showing parts of the mechanism of FIG. 14 in an open position and separated;

FIGS. 16 and 17 are perspective views of a ring latch mechanism forming a third embodiment of the invention, shown closed (FIG. 16) and opened and separated (FIG. 17);

FIG. 17 a is a scrap view showing an alternative form of latch lever end, and

FIG. 18 is a perspective view of a ring latch mechanism forming a fourth embodiment of the invention, with its parts opened and separated.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring initially to FIGS. 1-3, an injection mouldable, all-polymer securing ring 10 may be used to secure an injection moulded polymer lid 12 across the open end 14 of a fibreboard container 16. The lid 12 thereby closes the container 16 e.g. for the transport of powders or granular materials, or any other suitable bulk goods. The ring 10 comprises a radially outer wall 20 and a pair of side walls 22, 24 which define between them a radially inwardly open, circumferential groove 18. A rim 26 of the lid 12 may be trapped in the groove 18 together with a radially outwardly and upwardly directed end chime flange 28 of the container 16. The lid rim 26 may be shaped to provide a downwardly directed groove 27 in which the flange 28 is received, whereby the flange 28 is held in the lid rim groove 27 by the overlying ring 10 as shown in FIGS. 2 a, 2 b and 3. The ring side walls 22, 24 and hence the width of the groove 18 may taper in the radially outward direction, whereby as the ring 10 is tightened about the lid periphery 26 and container end chime flange 28, the latter are cammed into tighter engagement with one another so that the lid is held firmly in engagement with the container substantially around their entire mating circumferences. Optionally, a sealing gasket 30 may be housed in the lid rim groove 27 for circumferential sealing engagement with the container end chime flange 28.

As best seen in FIGS. 4-13, the ring 10 is provided with a latch mechanism 32, openable to allow the ring 10 to be circumferentially and radially expanded for removal from or fitment over the interengaged lid rim 26 and container end chime flange 28. In this position the ring 10 and lid 12 may be fitted to or removed from the container 16. The latch mechanism 32 can also be closed, to constrict the ring 10 circumferentially about the mating lid rim and container end chine flange 26/28, so as to clamp the lid securely in place to close the container 16.

As shown in FIGS. 4-13 the securing ring 10 comprises a first end 40, a second end 42 and a latch lever 44 which together form the latch mechanism 32. The latch lever 44 is movable between an open position in which the first and second ends of the ring are separated (thereby expanding the ring 10) and a closed position in which the first and second ends are drawn closer together (thereby constricting the ring 10). The latch lever 44 is connected to the first end 40 of the ring by a flexible connection which in this embodiment comprises a living hinge 46. As shown, the latch lever 44 comprises a top wall 48 and opposed side walls 50 defining a channel shaped hollow interior. With the latch lever in the closed position, the second end 42 of the ring is nestingly received in the hollow latch lever interior so that the closed latch mechanism presents a compact, low-profile form.

The side walls 50 of the latch lever 44 extend at 51 forwardly of the living hinge towards the very tip of the ring second end 42 when the latch lever is in the closed position. A pivot shaft 52 (whose end position is indicated schematically in dotted lines in FIGS. 6, 12 and 13) spans between the forward extensions 51 of the latch lever side walls 50. The ring first end 40 also has a forward extension 54 which is slightly curved to form a concentric continuation of the ring outer wall 20 at a slightly larger radius. With the latch lever 44 in its closed position, the ring first end extension 54 lies between the upper edges of the latch lever side wall extensions 51. The living hinge 46 connects the distal end of the ring first end extension 54 to the latch lever top wall 48 along a flexure line extending parallel to the ring axis. The latch lever 44 may therefore conveniently be integrally moulded with the ring first end 42. With the latch lever in the closed position, the ring first end extension 54 interdigitates with the latch lever side wall extensions 51, so that the latch lever is at least partially overlappingly received against the first end of the ring.

As best seen in FIGS. 10 and 11, the radially outer surface of the second end of the ring is provided with a pair of hook-shaped formations 60, placed symmetrically on either side of the ring axial centre plane. Tip portions 62 of the hook shaped formations 60 face rearwardly of the ring second end 42 and overlie the radially outer wall 20 to form a bearing recess 64 (see e.g. FIG. 13). The recess 64 preferably extends partially into the thickness of the ring radially outer wall 20 to reduce the overall height of the hook shaped formations 60. Similarly the underside of the ring first end extension 54 may contain two relieved areas for reception of upper parts of the respective hook shaped formations 60, whereby the overall radial dimension of the latch mechanism 32 is minimised. As best shown in FIGS. 10 and 11, the pivot shaft 52 is snap-fitted into and rotatingly received in the bearing recess 64. The ring first and second ends 40, 42 are thereby interconnected by the latch lever 44 so as to form the latch lever mechanism 32. FIG. 12 shows the latch lever rotated about the living hinge 46 and the pivot shaft 52 through in excess of 140 degrees from the closed position to the open position, so that the ring ends 40, 42 are separated from one another and the ring 10 is circumferentially and radially expanded. FIG. 13 shows the latch lever 44 in an open position, with the pivot shaft 52 disengaged from the bearing recess 64. FIGS. 10 and 11 in contrast show the latch lever 44 in the closed position in which the ring ends 40, 42 are drawn more closely together and the latch lever partially overlaps the first ring end 40. In particular, the latch lever side wall extensions 51 (not visible in FIGS. 12 and 13) overlap the ring first end extension 54.

Compared to the living hinge 46, the ring first end extension 54 is relatively stiff and will maintain its curvature even under quite substantial tensile loads. This curvature also ensures that the pivotal connection between the latch lever and the second end of the ring (in this case formed by the pivot shaft 52 and bearing surface 64) lies radially outwardly of the flexible connection (in this case the living hinge), whereby the line of action of hoop stress induced tensile force in the flexible connection extends radially inward of the pivotal connection. That is, the line of action of the tensile force transmitted through the living hinge 46 passes radially inwardly of the axis of the pivot shaft 52. The latch lever 44 therefore operates with an overcentre action and will remain stably in the closed position under ring tensile hoop stress imposed loading. No additional measures are required to hold the latch lever 44 in its nested position over the second ring end 42. However an eye 70 may be provided on the ring second end 42 radially outer surface 20 and apertures 72 may be provided in the lever side walls 50. The eye 70 and apertures 72 are brought into registration when the lever is in its closed position, for reception of a tamper indicating security pin, security tag or the like (not shown), in a manner familiar to those skilled in the art. For stress transfer directly between the interengaged ring ends 40, 42, a transverse wall 80 is provided, upstanding radially from the very tip of the second ring end 42, and engageable behind a radially depending web 82 which spans between the side walls 22, 24 inside the first ring end 20.

The latch mechanism shown in FIGS. 14, 14 a, 14 b and 15 is in many respects similar to that of FIGS. 4-13 described above, except that the pivotable connection between the latch lever 44 and the ring second end 42 differs, and the arrangement for transferring hoop stress directly between the ring ends 40, 42 when the latch is closed also differs.

The latch lever side wall extensions 51 are linked by a radially outer web 53 which is a continuation of the latch lever top wall 48 beneath the living hinge 46, and lies directly underneath the first ring end extension 54 when the latch mechanism 32 is closed. The web 53 terminates in an upwardly curled lip 55 (see FIGS. 14 a and 15). This may be received in a correspondingly curved slot 57 formed beneath a rearwardly facing nose 59 moulded on ring second end radially outer surface 20 to form a compressive force transmitting pivot connection between the latch lever 44 and the and the ring second end 42. When the curled lip 55 and curved slot 57 are interengaged, the lever side wall forward extensions 51 straddle the ring second end 42 and so help to maintain registration of the lip 55 and slot 57 axially of the ring 10. To further guide and maintain these pivot connection components 55/57 in proper registration, the inner surface of each lever side wall extension 51 may be provided with an arcuate depression or slot 63 (only one shown in the drawings; the ring being mirror symmetrical about the centre plane normal to the ring axis). Each slot 63 slidably receives and guides a respective protrusion 61 which is formed on the outer surface of each second ring end side wall 22, 24: see FIG. 15. Other forms of pivot may be used in place of the curled lip 55 and curved slot, such as a knife-edge bearing. The pivot connection 55/57 is of low profile, as is the living hinge 46, each contributing to a low radial profile of the latch mechanism 32 overall. The low profile of both pivot connections also enables an overcentre action to be maintained with only a very slight curvature in the first end extension 54. The number of overlapping layers in the region of the latch lever is minimised to two, both radially and axially of the ring, reducing the bulk of the latch mechanism in comparison to at least some prior art designs.

For hoop stress transmission from the first ring end 40 directly to the second ring end 42 when the latch mechanism is closed (thereby relieving stress on the other latch mechanism components, such as the latch lever 44, first ring end extension 54 and pivot connection 55/57), the top wall 20 of the ring first end 40 is provided with a post 65 which depends into the channel 18 through the ring first end 40. The post 65 has a cruciform slot which divides its distal end into four resilient legs, each with a radially protruding foot, which are snap-fittable through an aperture 67 formed in the outer wall 20 of the ring second end 42 as the two ring ends 40, 42 are levered into close proximity by the latch lever 44. The ring outer wall is preferably countersunk for reception of the feet on the post 65, so that these feet do not protrude into the ring groove 18 where they might interfere with the lid rim, container end flange or like components secured by the ring 10. See in particular FIG. 14 b.

In the latch mechanism 32 shown in FIGS. 16 and 17, the latch lever 44 is mounted to the ring first end 40 by a pair of flexible ligaments 81, one on either axial side of the ring 10 (only one shown in the drawings; the ring being mirror symmetrical about the centre plane normal to the ring axis). The ligaments 81 may be formed from braided yarns or fibres of nylon, polyester, polypropylene or other suitable high performance polymers known in the cordage art. In this case they are insert moulded so as to interconnect the latch lever 44 and ring first end 40. Alternatively, the ligaments 81 may be thin solid strands integrally moulded with and therefore formed from the same material as the ring first end 40 and latch lever 44.

As best shown in FIG. 17, ends of the latch lever side walls 50 which normally lie inside the groove 18 within the ring first end 40 when the latch is closed, are provided with part-circular bearing notches 68 (only one being visible in FIG. 17, but the other being identical, due to the above mentioned minor symmetry). The side walls 22, 24 of the ring second end 42 are each provided on the outside with a corresponding trunnion 66, which is snap-fittable into the corresponding notch 68 to form a pivotable connection between the latch lever 44 and the ring second end 42. The outer corner 74 of the ring second end is suitably rounded or chamfered for this purpose. Because the pivot axis through the trunnions 66 and notches 68 lies radially outwardly of the ligaments 80, the latch lever 44 operates with an overcentre action and remains stably in the closed position under ring tensile hoop stress imposed forces. However for additional security, and to allow direct force transmission between the ring first and second ends 40, 42, the ring first end is provided with a depending post 65 similar to that of FIGS. 14 and 15 as described above, but snap-fittable not only through an aperture 67 in the ring second end outer wall 20 (similar to aperture 67 described with reference to FIGS. 14, 14 b and 15), but also through an aperture 73 in the latch lever top wall 20. A similar post 69 may be provided inside the latch lever 44, for snap-fitment in a further similar aperture 71 provided in the ring second end 42 outer wall 20.

In a variant (not shown), the end of the latch lever containing the notches 68 is shortened so as to terminate short of or adjacent to the ring first end 40 when the latch lever 44 is in its closed position. In this way the maximum number of overlapping layers in the closed latch mechanism is reduced from three to two; the ring second end 42 being received directly in the ring first end 40 without any intervening latch lever layer. The post 65 may therefore engage directly with the aperture 67, without passing through the latch lever 44. To match the shortened latch lever 44, the trunnions 66 are moved further back from the tip of the ring second end 42, so that the ring second end 42 projects from the channel-shaped latch lever 44 and is received within the channel-shaped ring first end 40 when the latch lever 44 is in the closed position. The end of the top wall 48 of the latch lever 44 adjacent to the notches 68 may be relieved at 49 (see FIG. 17 a) so as not to interfere with the radially outer wall of the ring second end 42 as the latch lever 44 is opened. In either of these variants, the ligaments 81 may be replaced by an over moulded thin web made from flexible belt or strap type material such as nylon or polypropylene; this web joining the radially outer wall 48 of the latch lever 44 to the radially outer wall of the ring first end 40.

In FIG. 18, the latch lever 44 is again connected to an extension of the ring first end 40 by a living hinge 46. In this embodiment, the ring side walls 22, 24 are extended at the ring first end to form a yoke 84, the side wall extensions lying outward of the lever side walls 50. Lever side wall extensions 51 have upwardly curved ends which are spanned by a pivot shaft 90. The pivot shaft 90 is snap-engageable in a bearing recess 92 formed beneath a rearwardly facing hook-shaped formation 88 moulded onto the ring second end 42 outer wall 20. The pivotable connection 90/92 so formed will emerge through the aperture 86 defined between the yoke 84 side wall extensions when the lever 44 is pivoted to its closed position to overlie the ring second end 42. In this position the pivot shaft 90 will lie radially outward of the living hinge 46, so as to provide an overcentre movement of the latch mechanism 32. A direct interengagement between the ring ends 40, 42 may again be provided, e.g. by a snap-fit post and aperture arrangement 65/67, similar to FIG. 14-15 or 16-17, or by any other suitable arrangement, like the transverse wall 80 and depending web 82 arrangement of FIGS. 10-14.

The invention is not limited to the embodiments described above and may be carried into effect within the scope of the claims in many other ways. Any individual element or feature of any of the embodiments described above may be combined with or substituted for any other suitable element or feature of any other described embodiment. 

1. A securing ring for holding a lid or other closure on a container, the securing ring comprising: a first end; a second end; a latch lever movable between an open position in which the first and second ends are separated and a closed position in which the first and second ends are drawn closer together; and a flexible connection by which the latch lever is connected to the first end, wherein at least a part of the latch lever extends from the flexible connection in a direction of the first end when the latch lever is in the closed position, and wherein the second end of the securing ring is nestingly received in a hollow interior of the latch lever when the latch lever is in the closed position.
 2. The securing ring of claim 1, wherein the flexible connection comprises a living hinge.
 3. The securing ring of claim 2, wherein the living hinge comprises a flexible web extending along an axis of the living hinge and spanning between the first end of the securing ring and the latch lever.
 4. The securing ring of claim 1, wherein the flexible connection comprises at least one flexible strap.
 5. The securing ring of claim 4, wherein the flexible strap comprises a ligament integrally moulded to be made of the same material as, and continuous with, the first end of the securing ring and the latch lever.
 6. The securing ring of claim 4, wherein the flexible strap comprises a ligament insert moulded to interconnect the first end of the securing ring and the latch lever.
 7. The securing ring of claim 1, wherein the flexible connection is provided at a distal end of a circumferential extension of the first end of the securing ring.
 8. The securing ring of claim 7, wherein: the securing ring comprises a radially outer wall and a pair of side walls which define a radially inwardly open, circumferential groove between the radially outer wall and the pair of side walls, and the circumferential extension forms a continuation of the radially outer wall at the first end of the securing ring.
 9. The securing ring of claim 7, wherein: the securing ring comprises a radially outer wall and a pair of side walls which define a radially inwardly open, circumferential groove between the radially outer wall and the pair of side walls, and the circumferential extension forms a continuation of the pair of side walls at the first end of the securing ring.
 10. The securing ring of claim 1, wherein the flexible connection allows angular movement of the latch lever through at least 120 degrees with respect to the first end.
 11. The securing ring of claim 1, wherein the flexible connection allows angular movement of the latch lever through at least 140 degrees with respect to the first end.
 12. The securing ring of claim 1, wherein the latch lever is pivotally connected to the second end of the securing ring through a pivot connection.
 13. The securing ring of claim 12, wherein the pivot connection between the latch lever and the second end of the securing ring comprises a pivot shaft rotationally received in a pivot bearing.
 14. The securing ring of claim 13, wherein the pivot bearing comprises a hook-shaped formation formed on a radially outer surface of the second end of the securing ring.
 15. The securing ring of claim 12, wherein the pivot connection between the latch lever and the second end of the securing ring comprises a knife-edge bearing or a curled lip receivable in a curved slot.
 16. The securing ring of claim 12, wherein, when the latch lever in the closed position, the pivotal connection between the latch lever and the second end of the securing ring lies radially outwardly of the flexible connection.
 17. The securing ring of claim 1, wherein the first end, the second end and the latch lever form a latch mechanism having no more than two layers.
 18. A securing ring for holding a lid or other closure on a container, the securing ring comprising: a first end; a second end; a latch lever movable between an open position in which the first and second ends are separated and a closed position in which the first and second ends are drawn closer together; and a flexible connection by which the latch lever is connected to the first end, wherein the latch lever is pivotally connected to the second end of the securing ring through a pivot connection, and wherein, when the latch lever in the closed position, the pivotal connection between the latch lever and the second end of the securing ring lies radially outwardly of the flexible connection.
 19. The securing ring of claim 18, wherein the flexible connection comprises a living hinge.
 20. The securing ring of claim 18, wherein the flexible connection is provided at a distal end of a circumferential extension of the first end of the securing ring.
 21. The securing ring of claim 18, wherein the flexible connection comprises at least one flexible strap or ligament.
 22. The securing ring of claim 18, wherein the first end, the second end and the latch lever form a latch mechanism having no more than two layers.
 23. A securing ring for holding a lid or other closure on a container, the securing ring comprising: a first end; a second end; a latch lever movable between an open position in which the first and second ends are separated and a closed position in which the first and second ends are drawn closer together, the latch lever being at least partially overlappingly received against the first end of the securing ring; and a living hinge by which the latch lever is connected to the first end.
 24. The securing ring of claim 23, wherein the living hinge is provided at a distal end of a circumferential extension of the first end of the securing ring.
 25. The securing ring of claim 1, wherein the securing ring is made of a plastic. 